1. Field of the Invention
The invention concerns a pumping device for wells, such as oil wells, comprising a framework or rig and machinery capable of imparting, by the intermediation of a flexible connection, a reciprocating rising and falling movement to a set of rods or links whereby to actuate a force pump immersed in the well.
2. Description of the Prior Art
Pumping devices of this kind are known, e.g. from German Pat. No. 814,832 and U.S. Pat. No. 1,839,355, wherein the framework has, for the connection to the set of rods, at least one guide pulley with a horizontal axis of rotation carried on an arm for pivoting on the framework about a vertical axis.
However, these devices consist of lattice frameworks. In order to give the necessary strength to such frameworks, they must be fairly large and they thus occupy a relatively large surface area. Moreover, they are expensive to maintain, especially in a marine environment, and in use it is difficult to release the head of the well for servicing work. In addition, lattice frameworks do not permit a large pivotal angle to be achieved by the pivoting arm.